Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From reactant having a halogen atom or oxygen single bonded...
Reexamination Certificate
2002-03-08
2004-08-17
Buttner, David J. (Department: 1712)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From reactant having a halogen atom or oxygen single bonded...
C528S200000, C528S201000, C528S370000
Reexamination Certificate
active
06777528
ABSTRACT:
BACKGROUND OF THE INVENTION
1) Field of the Invention
The present invention relates to a process for producing a polycarbonate resin with both good transparency and good color which is not colored during its production.
2) Prior Art
A polycarbonate resin obtained by melt polycondensation of pentacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) with carbonic acid diester, as shown in Japanese Patent Kokai (Laid-open) No. 2000-302860, is excellent in transparency, heat resistance, impact resistance and possesses a low photoelastic constant and a good balance between refractive index and Abbe's number.
Thus, this polycarbonate resin is suitably applicable to plastic optical products such as optical disc substrates, various lenses, prisms, optical fibers and photoconductive boards.
However, when a catalyst such as basic compounds including alkaline metal compounds, alkaline earth metal compounds and nitrogen- or phosphorus-containing compounds described in Japanese Patent Kokai (Laid-open) No. 2000-302860 was used in the production, there caused problems that it was difficult to obtain a polycarbonate resin product with good color since the polycarbonate resin was readily colored during melt polycondensation.
A polycarbonate resin obtained by melt polycondensation of petacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) and alicyclic diol represented by the general foumula (4) with carbonic acid diester, as shown in Japanese Patent Kokai (Laid-open) No. 2001-11168, is excellent in transparency, heat resistance, flowability and possesses a low photoelastic constant and a good balance between refractive index and Abbe's number.
Thus, this polycarbonate resin is suitably applicable to plastic optical products such as optical disc substrates, various lenses, prisms, optical fibers and photoconductive boards.
However, when a catalyst such as basic compounds including alkaline metal compounds, alkaline earth metal compounds and nitrogen- or phosphorus-containing compounds described in Japanese Patent Kokai (Laid-open) No. 2001-11168 was used in the production, there caused problems that it was difficult to obtain a polycarbonate resin product with good color since the polycarbonate resin was readily colored during melt polycondensation.
A polycarbonate resin obtained by melt polycondensation of pentacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) and alicyclic diol represented by the general formula (5) with carbonic acid diester, as shown in Japanese Patent Kokai (Laid-open) No. 2001-11166, is excellent in transparency, heat resistance, flowability and possesses a low photoelastic constant and a good balance between refractive index and Abbe's number.
Thus, this polycarbonate resin is suitably applicable to plastic optical products such as optical disc substrates, various lenses, prisms, optical fibers and photoconductive boards.
However, when a catalyst such as basic compounds including alkaline metal compounds, alkaline earth metal compounds and nitrogen- or phosphorus-containing compounds described in Japanese Patent Kokai (Laid-open) No. 2001-11166 was used in the production, there caused problems that it was difficult to obtain a polycarbonate resin product with good color since the polycarbonate resin was readily colored during melt polycondensation.
A polycarbonate resin obtained by melt polycondensation of pentacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) and alicyclic diol represented by the general formula (6) with carbonic acid diester, as shown in Japanese Patent Kokai (Laid-open) No. 2001-11165, is excellent in transparency, heat resistance, flowability and possesses a low photoelastic constant and a good balance between refractive index and Abbe's number.
Thus, this polycarbonate resin is suitably applicable to plastic optical products such as optical disc substrates, various lenses, prisms, optical fibers and photoconductive boards.
However, when a catalyst such as basic compounds including alkaline metal compounds, alkaline earth metal compounds and nitrogen- or phosphorus-containing compounds described in Japanese Patent Kokai (Laid-open) No. 2001-11165 was used in the production, there caused problems that it was difficult to obtain a polycarbonate resin product with good color since the polycarbonate resin was readily colored during melt polycondensation.
A polycarbonate resin obtained by melt polycondensation of pentacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) and alicyclic diol represented by the general formula (7) with carbonic acid diester, as shown in Japanese Patent Kokai (Laid-open) No. 2001-11169, is excellent in transparency, heat resistance, flowability and possesses a low photoelastic constant and a good balance between refractive index and Abbe's number.
Thus, this polycarbonate resin is suitably applicable to plastic optical products such as optical disc substrates, various lenses, prisms, optical fibers and photoconductive boards.
However, when a catalyst such as basic compounds including alkaline metal compounds, alkaline earth metal compounds and nitrogen- or phosphorus-containing compounds described in Japanese Patent Kokai (Laid-open) No. 2001-11169 was used in the production, there causes problems that it was difficult to obtain a polycarbonate resin product with good color since the polycarbonate resin was readily colored during melt polycondensation.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the above-mentioned prior art problems and to provide a process for producing a polycarboante resin with good transparency and good color which is not colored during its production.
As a result of extensive studies to solve the above-mentioned prior art problems, the inventors have found that the above-mentioned problems can be solved by a process for producing a polycarbonate resin which comprises performing melt polycondensation of pentacyclopentadecanedimethanol represented by the following general formula (1) and/or the following general formula (2) or pentacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) and diol represented by the following general formula (3) with carbonic acid diester in the presence of a catalyst containing at least one compound selected from the group consisting of zinc compounds, tin compounds, lead compounds, zirconium compounds and hafnium compounds;
wherein X is an alkylene group having 3 to 14 carbon atoms or a cycloalkylene group having 4 to 14 carbon atoms, and have accomplished the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in more detail below.
Pentacyclopentadecanedimethanol represented by the general formula (1) and/or the general formula (2) is hereinafter abbreviated as “PCPDM”.
Examples of diol represented by the general formula (3) include tricyclo(5.2.1.0
2,6
) decanedimethanol, norbornane dimethanol, decaline-2,6-dimethanol, cyclohexane-1,4-dimethanol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol and 1,14-tetradecanediol.
The molar ratio (diol/PCPDM) of diol represented by the general formula (3) to PCPDM is preferably 0 to 2.3 from the aspect of heat resistance and more preferably 0 to 1. PCPDM, tricyclo(5.2.1.0
2,6
) decanedimethanol, norbornane dimethanol, decaline-2,6-dimethanol and cyclohexane-1,4-dimethanol include all isomers thereof in the range of their structural formulas. Further, it is preferable that all the diols to be used have a high purity as much as possible.
As the catalyst to be used in the present invention, least one compound selected from the group consisting of zinc compounds, tin compounds, lead compounds, zirconium compounds and hafnium compounds is
Fujimori Takayasu
Mizukami Masamichi
Ohgi Hiroaki
Buttner David J.
Mitsubishi Gas Chemical Company Inc.
Sughrue & Mion, PLLC
LandOfFree
Process for producing polycarbonate resin does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for producing polycarbonate resin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for producing polycarbonate resin will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3321994